CN106717075B

CN106717075B - Dynamic directional synchronization signals in wireless communication systems

Info

Publication number: CN106717075B
Application number: CN201580050361.XA
Authority: CN
Inventors: O·阿亚什; S·苏布拉玛尼安; A·桑佩斯; 厉隽怿
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2014-09-19
Filing date: 2015-08-24
Publication date: 2020-02-14
Anticipated expiration: 2035-08-24
Also published as: KR101960205B1; WO2016043930A1; US20160087743A1; BR112017005529A2; JP2017533615A; EP3195670B1; US9496975B2; EP3195670A1; JP6517323B2; CN106717075A; KR20170057267A

Abstract

Methods, systems, and devices for dynamic directional synchronization signal signals in millimeter wave communication systems are described. The base station may determine a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communications. The base station may identify network characteristics of the millimeter wave communication network and adjust parameters of the narrowband signal and/or wideband signal component in the synchronization signal. The parameters may include transmit power division or ratio, bandwidth, tone selection, or a combination thereof.

Description

Dynamic directional synchronization signals in wireless communication systems

Cross-referencing

The present application claims priority from U.S. patent application No.14/624,742 to El Ayach et al, entitled "Dynamic Direction synchronization Signals in Wireless Communications," filed on 18.2.2015; and U.S. provisional patent application No.62/052,927 by El Ayach et al, entitled "Dynamic Direction synchronization Signals in Wireless Communications," filed on 9/19 2014; the above applications are assigned to the assignee of the present application.

Technical Field

The present disclosure relates to wireless communication systems, and more particularly, to dynamic directional synchronization signals in wireless communications.

Background

Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems.

As an example, a wireless multiple-access communication system may include several base stations, each of which simultaneously supports communication for multiple communication devices, otherwise referred to as User Equipments (UEs). A base station may communicate with a UE on downlink channels (e.g., for transmissions from the base station to the UE) and uplink channels (e.g., for transmissions from the UE to the base station). The UE may locate the base station by detecting a synchronization signal from which the UE acquires a base station identity code (cell ID), system timing information, frame alignment information, and the like. In systems where the receiver is high signal strength and noise limited (e.g., millimeter wave systems), the beamformed synchronization signal may sweep through the cell coverage area to provide coverage enhancement to improve detection.

A wireless communication system employing a dual signal synchronization scheme may include a narrowband signal of high power and a wideband signal of low power. However, aspects may make the detection of narrowband signals more or less reliable than the detection of wideband signals. For example, a higher power narrowband signal may travel farther than a lower power wideband signal. Other factors that may affect detection may include the geographic coverage area of the millimeter wave cell, the density of UEs and/or base stations within the cell, UE configuration, interference, and so forth. Thus, a fixed narrowband/wideband signal configuration may not be ideal in any situation.

Disclosure of Invention

The described features generally relate to one or more improved systems, methods, and/or apparatuses for dynamic directional synchronization signals in wireless communications. In some examples, a base station may determine a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communications, where one or more parameters of the narrowband and/or wideband signal may be adjusted. Characteristics associated with the millimeter wave communication network may also be determined, such as a level of timing synchronization between UEs, detection of an incorrect synchronization signal by a UE, and so forth. Parameters of the narrowband signal and/or the wideband signal may be dynamically adjusted based on network characteristics. For example, the power separation between the narrowband signal and the wideband signal may be adjusted (e.g., one transmit power is increased and the other transmit power is decreased). In another example, the bandwidth of the wideband signal may be adjusted (e.g., increased or decreased) based on the characteristic. Thus, the synchronization signal component can be dynamically adjusted to take into account network characteristics and improve detection.

A method of wireless communication at a wireless device is described. The method can comprise the following steps: determining a narrowband signal component and a wideband signal component in a synchronization signal of a millimeter wave communication network; identifying one or more characteristics associated with the millimeter wave communication network; and selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic.

An apparatus for wireless communication at a wireless device is described. The apparatus may include: means for determining a narrowband signal component and a wideband signal component in a synchronization signal of a millimeter wave communication network; means for identifying one or more characteristics associated with the millimeter-wave communication network; and means for selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic.

An apparatus for wireless communication at a wireless device is described. The apparatus may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory, wherein the instructions are executable by the processor to: determining a narrowband signal component and a wideband signal component in a synchronization signal of a millimeter wave communication network; identifying one or more characteristics associated with the millimeter wave communication network; and selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic.

A non-transitory computer-readable medium storing computer executable code for wireless communication at a wireless device is described. The code is executable by a processor to: determining a narrowband signal component and a wideband signal component in a synchronization signal of a millimeter wave communication network; identifying one or more characteristics associated with the millimeter wave communication network; and selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic.

In some examples of the above-described method, apparatus, or non-transitory computer-readable medium, adjusting the at least one parameter comprises adjusting a transmit power distinction between the narrowband signal component and the wideband signal component. Additionally or alternatively, in some examples the transmit power distinguishes a ratio of a first transmit power comprising the narrowband signal component to a second transmit power of the wideband signal component.

Some examples of the above-described method, apparatus, or non-transitory computer-readable medium may further include: identifying, by one or more User Equipments (UEs) located at an edge of a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a reduction in the narrowband signal component monitored; increasing a first transmit power of the narrowband signal component based at least in part on the identified reduction; and reducing a second transmit power of the wideband signal component based at least in part on the identified reduction. Additionally or alternatively, some examples may include: receiving information indicating a predefined level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component, and selectively adjusting the parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the level of timing synchronization.

In some examples of the above-described method, apparatus, or non-transitory computer-readable medium, the one or more characteristics include one or more of: a level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a false alarm rate associated with the one or more UEs detecting an incorrect synchronization signal, a distribution of UEs entering the coverage area of the source, or a combination thereof. Additionally or alternatively, in some examples adjusting the at least one parameter comprises adjusting a bandwidth of the wideband signal component.

Some examples of the above-described method, apparatus, or non-transitory computer-readable medium may further include: increasing the bandwidth of the wideband signal component based at least in part on a determination that a path loss is above a predefined threshold or a level of frequency selection exceeds a predefined value. Additionally or alternatively, some examples may include: increasing the bandwidth of the wideband signal component based at least in part on a determination that the wideband signal component is being used by at least one user equipment for channel estimation.

Some examples of the above method, apparatus, or non-transitory computer-readable medium, adjusting the at least one parameter comprises at least one of: transmitting the wideband signal component on consecutive tones, transmitting the wideband signal component on alternating tones, transmitting the wideband signal component on non-uniform tones, or a combination thereof. Additionally or alternatively, in some examples, identifying the one or more characteristics includes one or more of: receive feedback signals from one or more User Equipments (UEs) communicating via the millimeter wave wireless communication system, receive feedback signals from one or more other sources in the millimeter wave wireless communication system, receive feedback signals from one or more base stations in a non-millimeter wave wireless communication system, or a combination thereof.

In some examples of the above-described method, apparatus, or non-transitory computer-readable medium, the narrowband signal component comprises a beacon signal and the wideband signal component comprises a wideband signal. Additionally or alternatively, in some examples, the wideband signal includes a Zadoff-Chu sequence.

In some examples of the above-described methods, apparatus, or non-transitory computer-readable media, the narrowband signal component and the wideband signal component of the synchronization signal are directionally transmitted via one or more beamformed signals.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The nature of the concepts disclosed herein (both as to its organization and method of operation), together with the advantages associated therewith, will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the claims.

Drawings

A further understanding of the nature and advantages of the present invention may be realized by reference to the following drawings. In the drawings, similar components or features may have the same reference numerals. In addition, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. As long as the first reference numeral is used in the description, the description may be applicable to any one of the similar components having the same first reference numeral regardless of the second reference numeral.

Fig. 1 illustrates a block diagram of a wireless communication system, in accordance with various aspects of the present disclosure;

fig. 2 shows a block diagram of a device configured for use in wireless communications, in accordance with various aspects of the present disclosure;

fig. 3 shows a block diagram of a device configured for use in wireless communications, in accordance with various aspects of the present disclosure;

fig. 4 shows a block diagram of a device configured for use in wireless communications, in accordance with various aspects of the present disclosure;

fig. 5 illustrates a block diagram of a wireless communication system in accordance with various aspects of the disclosure;

fig. 6 shows a flow diagram (swim diagram) illustrating aspects of a dynamic directional synchronization signal in wireless communications, in accordance with various aspects of the present disclosure;

fig. 7A-7E illustrate diagrams of exemplary dual component synchronization signals, in accordance with various aspects of the present disclosure;

fig. 8 shows a flow diagram illustrating aspects of a dynamic directional synchronization signal in wireless communications, in accordance with various aspects of the present disclosure;

fig. 9 is a flow diagram illustrating an example of a method for wireless communication, in accordance with various aspects of the present disclosure;

fig. 10 is a flow diagram illustrating an example of a method for wireless communication, in accordance with various aspects of the present disclosure; and

fig. 11 is a flow diagram illustrating an example of a method for wireless communication, in accordance with various aspects of the present disclosure.

Detailed Description

In a high frequency system (e.g., a millimeter wave communication system), a base station may employ a two component synchronous signal scheme in which two signals are transmitted. A narrowband signal, which typically has a higher transmit power spectral density than a wideband signal, may be transmitted as well as the wideband signal. The combination of the narrowband signal and the wideband signal component of the synchronization signal typically conveys timing information, a cell ID, and/or various other parameters associated with the wireless communication system. However, for various reasons, these two components of the synchronization signal may not be equally detectable by the UE. For example, higher power narrowband signals may travel farther than lower power wideband signals, and thus, it may be difficult for UEs at the edge of the cell coverage area to detect wideband signals. The terrain and/or environment within the coverage area of a cell may have more impact on the monitoring of one component than another. Currently, there is no mechanism for the base station (or source cell) of the synchronization signal to dynamically adjust the parameters of the narrowband signal and/or the wideband signal based on network characteristics to provide reliable detection of both synchronization signal components.

According to aspects of the present description, parameters of narrowband signals and/or wideband signal components in synchronization signals for millimeter wave communication may be dynamically adjusted based on various characteristics of the millimeter wave communication network. The base station (or source cell) may determine the narrowband signal and the wideband signal of the synchronization signal. The base station may identify characteristics associated with the millimeter-wave communication network. For example, a base station may receive feedback signals from other UEs within its coverage area indicating channel conditions and/or interference, receive feedback signals from other base stations (both millimeter wave and non-millimeter wave base stations), or a combination thereof. In some examples, the base station may determine the one or more characteristics based on internal factors. Based on these characteristics, the base station may adjust one, some, or all of these parameters of the narrowband signal and/or the wideband signal to improve detection of both components of the synchronization signal. The base station may adjust the parameters once periodically based on scheduling (schedule) and/or in real time (or dynamically) as network characteristics change. In some examples, the base station may adjust parameters to achieve goals other than pure detection of both signal components, e.g., improve channel estimation by the UE using more wideband signals than narrowband signals, and vice versa.

According to additional aspects of the disclosure, the base station may vary the power discrimination between the narrowband signal and the wideband signal. For example, for a fixed or predefined transmit power of both signals, the base station may increase the transmit power of the narrowband signal and decrease the transmit power of the wideband signal, or vice versa. In other examples, the base station may adjust the bandwidth of the wideband signal component. For example, the base station may cause the wideband signal to have a wider bandwidth or a narrower bandwidth. In addition, the base station may adjust the wideband signal to transmit on consecutive tones, or on alternating (every other) tones, or some other predefined scheme.

The following description provides examples, and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the described methods may be performed in an order different than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined in other examples.

Fig. 1 illustrates an example of a wireless communication system 100 in accordance with various aspects of the disclosure. The wireless communication system 100 includes base stations 105, UEs 115, and a core network 130. The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The base station 105 interfaces with the core network 130 over a backhaul link 132 (e.g., S1, etc.) and may perform wireless configuration and scheduling to communicate with the UE 115 or may operate under the control of a base station controller (not shown). In various examples, the base stations 105 can communicate with each other directly or indirectly (e.g., through the core network 130) over backhaul links 134 (e.g., X1, etc.), which backhaul links 134 can be wired or wireless communication links.

The base station 105 may wirelessly communicate with the UE 115 via one or more base station antennas. Each base station 105 site may provide communication coverage for a respective geographic coverage area 110. In some examples, the base station 105 may be referred to as a base transceiver station, a wireless base station, an access point, a wireless transceiver, a node B, eNodeB (eNB), a home nodeb, a home eNodeB, or some other suitable terminology. The geographic coverage area 110 of a base station 105 can be divided into sectors that form only a portion of the coverage area (not shown). The wireless communication system 100 may include different types of base stations 105 (e.g., macro and/or small cell base stations). For different technologies (e.g., LTE/LTE-a, mm wave, etc.), there may be overlapping geographic coverage areas 110.

In some examples, the wireless communication system 100 is an LTE/LTE-a network. In an LTE/LTE-a network, the term "evolved node b (enb)" may be used generally to describe the base station 105, while the term UE may be used generally to describe the UE 115. The wireless communication system 100 may be a heterogeneous LTE/LTE-a network in which different types of enbs provide coverage for various geographic areas. For example, each eNB or base station 105 may provide communication coverage for a macro cell, a small cell, and/or other types of cells. The term "cell" is a 3GPP term that can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on the context. In some examples, the wireless communication system 100 may be or include a millimeter wave communication network having one or more base stations 105 in communication with the UE 115.

A macro cell typically covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription with the network provider. A small cell is a lower power base station than a macro cell, which may operate in the same or different frequency band (e.g., licensed, unlicensed, etc.) as the macro cell. According to various examples, the small cells may include pico cells, femto cells, and micro cells. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription with the network provider. A femto cell may also cover a relatively small geographic area (e.g., a home) and may provide restricted access by UEs having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for users in the home, etc.). The eNB for the macro cell may be referred to as a macro eNB. An eNB for a small cell may be referred to as a small cell eNB, pico eNB, femto eNB, or home eNB. An eNB may support one or more (e.g., two, three, four, etc.) cells (e.g., component carriers).

The wireless communication system 100 may support synchronous operation or asynchronous operation. For synchronous operation, the base stations may have similar frame timing, and transmissions from different base stations may be approximately aligned in time. For asynchronous operation, the base stations may have different frame timings, and transmissions from different base stations may not be aligned in time. The techniques described herein may be used for synchronous or asynchronous operations.

A communication network that may accommodate some of the various disclosed examples may be a packet-based network operating according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. The Radio Link Control (RLC) layer may perform packet segmentation and reassembly for communication on logical channels. A Medium Access Control (MAC) layer may perform priority processing and multiplexing of logical channels to transport channels. The MAC layer may also use hybrid arq (harq) to provide retransmissions at the MAC layer to improve link efficiency. In the control plane, a Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of RRC connections between the UE 115 and the base station 105 or core network 130 of radio bearers supporting user plane data. At the Physical (PHY) layer, transport channels may be mapped to physical channels.

UEs 115 are dispersed throughout the wireless communication system 100, and each UE 115 may be stationary or mobile. The UE 115 may also include or be referred to by those skilled in the art as: a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. The UE 115 may be a cellular telephone, a Personal Digital Assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless telephone, a Wireless Local Loop (WLL) station, and so forth. The UE 115 may be capable of communicating with various types of base stations and network devices, including macro enbs, small cell enbs, relay base stations, and the like. UE 115 may also be able to communicate with other UEs within or outside the same coverage area of the base station via D2D communication.

The communication links 125 shown in the wireless communication system 100 may include Uplink (UL) transmissions from the UEs 115 to the base station 105 and/or Downlink (DL) transmissions from the base station 105 to the UEs 115. Downlink transmissions may also be referred to as forward link transmissions, and uplink transmissions may also be referred to as reverse link transmissions. Each communication link 125 may include one or more carriers, where each carrier may be a signal composed of multiple subcarriers (e.g., waveform signals of different frequencies) modulated according to the various wireless technologies described above. Each modulated signal may be transmitted on a different subcarrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, and so on. Communication link 125 may transmit bi-directional communications using FDD (e.g., using paired spectrum resources) or TDD operation (e.g., using unpaired spectrum resources). Frame structures for FDD (e.g., frame structure type 1) and TDD (e.g., frame structure type 2) may be defined.

In some embodiments of the system 100, the base station 105 and/or the UE 115 may include multiple antennas for employing an antenna diversity scheme to improve the quality and reliability of communications between the base station 105 and the UE 115. Additionally or alternatively, the base station 105 and/or the UE 115 may employ multiple-input multiple-output (MIMO) techniques, which may utilize a multipath environment to transmit multiple spatial layers carrying the same or different encoded data.

Wireless communication system 100 may support dynamic directional synchronization signals for millimeter wave detection and synchronization. For example, the millimeter-wave base station 105 may determine narrowband and wideband signal components of the synchronization signal and directionally transmit (e.g., beamform) the synchronization signal in a scanning mode to the UEs 115 within its coverage area 110. The base station 105 may configure the narrowband signal in the synchronization signal to convey location and other parameter information of the wideband signal in the synchronization signal. The base station 105 may link the wideband signal to the location of the narrowband signal. The base station 105 may identify one or more characteristics of the millimeter-wave network, such as path loss, interference, timing synchronization, and so forth. Based on the identified characteristics, the base station 105 may adjust parameters of the narrowband signal component and/or the wideband signal component. As one example, a base station may receive feedback from other base stations indicating that a high degree of timing synchronization exists between UEs within the coverage area and, based on this information, increase the transmit power of the narrowband signal and decrease (or even eliminate) the transmit power of the wideband signal component.

Fig. 2 shows a block diagram 200 of a device 105-a for use in wireless communications, in accordance with various aspects of the present disclosure. Device 105-a may be an example of one or more aspects of base station 105 described with reference to fig. 1. The device 105-a may include a receiver module 205, a synchronization management module 210, and/or a transmitter module 215. The device 105-a may also be or include a processor (not shown). Each of these modules may communicate with each other.

The components of device 105-a may be implemented individually or collectively using one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores), on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured/platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs) may be used that may be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in a memory, formatted to be executed by one or more general or special purpose processors.

The receiver module 205 can receive information such as packets associated with various information channels (e.g., control channels, data channels, etc.), user data, and/or control information. The receiver module 205 may receive messages from the millimeter wave UEs 115 that include information associated with synchronization signaling, access procedures, and the like. The information may be passed to the synchronization management module 210 and other components of the device 105-a.

The synchronization management module 210 may manage synchronization functions of the device 105-a. The synchronization management module 210 may determine a narrowband signal and a wideband signal for a synchronization signal in millimeter wave communications. The synchronization management module 210 may identify characteristics associated with the millimeter-wave communication network via, for example, the receiver module 205 and/or the transmitter module 215. Synchronization management module 210 may adjust parameters of the narrowband signal, the wideband signal, or a combination thereof based on the characteristic. For example, synchronization management module 210 may change the transmit power level, adjust the bandwidth, etc., for narrowband and wideband signal components in the synchronization signal.

The transmitter module 215 may transmit one or more signals received from other components of the device 115-a. The transmitter module 215 may transmit information such as packets, user data, and/or control information to the serving cell. The transmitter module 215 may transmit one or more signals of the millimeter wave UEs 115 in conjunction with various synchronization signaling operations, random access procedures, and so on. In some examples, the transmitter module 215 may be collocated with the receiver module 205 in the transceiver module 205.

Fig. 3 shows a block diagram 300 of a device 105-b for use in wireless communications, in accordance with various examples. Device 105-b may be an example of one or more aspects of base station 105 described with reference to fig. 1. It may also be an example of the device 105-a described with reference to fig. 1. The device 105-b may include a receiver module 205-a, a synchronization management module 210-a, and/or a transmitter module 215-a, which may be examples of respective modules of the device 105-a. Device 105-b may also include a processor (not shown). Each of these components may communicate with each other. The synchronization management module 210-a may include a network characteristics module 305 and a synchronization signal determination module 310. The receiver module 205-a and the transmitter module 215-a may perform the functions of the receiver module 205 and the transmitter module 215, respectively, of fig. 2.

The components of device 105-b may be implemented individually or collectively using one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores), on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured/platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs) may be used that may be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in a memory, formatted to be executed by one or more general or special purpose processors.

Network characteristics module 305 may manage aspects of network characteristics determination and management of device 105-b. The network characteristics module 305 may cooperate with the receiver module 205-a and/or the transmitter module 215-a to receive feedback signals from millimeter wave and non-millimeter wave base stations 105 from UEs within the coverage area of the device 105-b and/or to determine various network characteristics based on internal data. Example network characteristics may include path loss values, interference values and/or sources, timing synchronization levels, coverage area sizes, density of UEs 115 and/or base stations 105 within a coverage area, or a combination thereof. The network characteristics may generally identify propagation characteristics within the coverage area of device 105-b, for example. The network characteristics may also indicate a level of synchronization required for the UEs 115 within the coverage area.

The synchronization signal determination module 310 may manage aspects of the synchronization signaling for the device 105-b. For example, the synchronization signal determination module 310, in cooperation with the network characteristics module 305 and/or the transmitter module 215-a, may determine narrowband and wideband signal components in a synchronization signal for millimeter wave communications. The synchronization signal determination module 310 may communicate with the network characteristics module 305 to determine whether and which parameters of the narrowband signal and/or the wideband signal are to be adjusted to overcome or adapt to the current characteristics of the millimeter-wave network. Based on the network characteristics identified by the network characteristics module 305, the synchronization signal determination module 310 may adjust appropriate parameters (e.g., power, bandwidth, frequency selection/hopping pattern, etc.) of the narrowband signal and/or the wideband signal. The synchronization signal determination module 310 may cooperate with the transmitter module 215-a to transmit narrowband signals and wideband signals of the synchronization signal to UEs within its coverage area.

Fig. 4 shows a block diagram 400 of a device 105-c for use in wireless communications, in accordance with various examples. Device 105-c may be an example of one or more aspects of base station 105 described with reference to fig. 1. It may also be an example of the devices 105-a and/or 105-b described with reference to fig. 2 and 3. The device 105-c may include a receiver module 205-b, a synchronization management module 210-b, and/or a transmitter module 215-b, which may be examples of respective modules of the device 105-a and/or 105-b. The device 105-c may also include a processor (not shown). Each of these components may communicate with each other. The synchronization management module 210-b may include a network characteristics module 305-a and a synchronization signal determination module 310-a. The receiver module 205-b and the transmitter module 215-b may perform the functions of the receiver module 205 and the transmitter module 215, respectively, of fig. 2.

The components of device 105-c may be implemented individually or collectively using one or more Application Specific Integrated Circuits (ASICs) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores), on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured/platform ASICs, Field Programmable Gate Arrays (FPGAs), and other semi-custom ICs) may be used that may be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in a memory, formatted to be executed by one or more general or special purpose processors.

Network characteristics module 305-a may include a narrowband signal management module 405 and a wideband signal management module 410 and may manage aspects of synchronization signal identification and management for device 105-c. Narrowband signal management module 405 may receive feedback signals from one or more components of a millimeter-wave communication network and/or components of a different communication network via receiver module 205-b. Based on the feedback signal, narrowband signal management module 405 may determine a network characteristic of the narrowband signal component in the synchronization signal. For example, narrowband signal management module 405 may identify channel characteristics, timing synchronization levels, error detection rates, etc., of narrowband signal components in the synchronization signal. In some examples, narrowband signal management module 405 may determine that a narrowband signal is being received by other components, needed for various synchronization functions, and so on. Narrowband signal management module 405 may output information to, for example, synchronization signal determination module 310-a indicating network characteristics about narrowband signal components in the synchronization signal.

Broadband signal management module 410 may receive feedback signals from one or more components of the millimeter-wave communication network and/or components of a different communication network via receiver module 205-b. Based on the feedback signal, the wideband signal management module 410 may determine a network characteristic of the wideband signal component in the synchronization signal. For example, wideband signal management module 410 may identify channel characteristics, timing synchronization levels, error detection rates, etc. of wideband signal components in the synchronization signal. In some examples, broadband signal management module 410 may determine that broadband signals are being received by other components, needed for various synchronization functions. The wideband signal management module 410 may output information to, for example, the synchronization signal determination module 310 indicating network characteristics regarding the wideband signal component of the synchronization signal.

The synchronization signal determination module 310-a may include a power discrimination control module 415 and a bandwidth control module 420 and may manage aspects of the synchronization signal determination and adjustment operations of the device 105-c. The power discrimination control module 415 may cooperate with the network characteristics module 305-a to determine the transmit power of the narrowband signal and the wideband signal. For example, device 105-b may determine narrowband signal and wideband signal parameters (e.g., transmit power, frequency, bandwidth, etc.), and adjust one or more of these parameters based on the network characteristics. The power discrimination control module 415 may adjust the transmit power of the narrowband signal and the transmit power of the wideband signal. In some examples, device 105-b may allocate a fixed or maximum transmit power limit for synchronization signal transmission. In such an example, the power division control module 415 may adjust the transmit power levels of the narrowband signal and the wideband signal by dividing the available transmit power. That is, the ratio of the transmit power of the narrowband signal and the wideband signal may be adjusted based on the identified network characteristic.

The bandwidth control module 420 may, in cooperation with the network characteristics module 305-a, manage aspects of bandwidth allocation for synchronization signal transmission. For example, the bandwidth control module may adjust the bandwidth of the narrowband signal, the wideband signal, or both based on the identified network characteristic. In some network environments, bandwidth control module 420 may increase or decrease the bandwidth of the broadband signal. The bandwidth control module 420 may also determine which location (e.g., frequency, time, etc.) is used for transmission of the synchronization signal component. For example, bandwidth control module 420 may assign continuous frequencies or tones to the wideband signal, assign alternating (e.g., every other tone available) frequencies or tones to the wideband signal, or may assign uneven frequency allocations to the wideband signal. In some examples, bandwidth control module 420 may determine a frequency hopping pattern for the wideband signal.

Fig. 5 shows a block diagram 500 of a base station 105-d (e.g., a base station forming a portion or all of an eNB) for use in wireless communications, in accordance with various aspects of the disclosure. In some examples, the base station 105-d may be an example of aspects of one or more of the base stations 105 described with reference to fig. 1, fig. 2, fig. 3, or fig. 4 and/or aspects of one or more of the devices 105 (when configured as base stations) described with reference to fig. 2, fig. 3, or fig. 4. Base station 105-d may implement or facilitate at least some of the base station and/or device features and functions described with reference to fig. 1, 2, 3, or 4.

The base station 105-d may include a base station processor module 570, a base station memory module 580, at least one base station transceiver module (represented by base station transceiver module 550), at least one base station antenna (represented by base station antenna 545), and/or a synchronization signal determination module 510. The base station 105-d may also include one or more of a base station communication module 565 and/or a network communication module 575. Each of these modules may communicate with each other, directly or indirectly, over one or more buses 590.

The base station memory module 580 may include Random Access Memory (RAM) and/or Read Only Memory (ROM). The base station memory module 580 may store computer-readable computer-executable software/firmware code 585 containing instructions that, when executed, cause the base station processor module 570 to perform various functions related to wireless communications described herein (e.g., determining wideband and narrowband signal components in a synchronization signal, adjusting parameters of a signal component based on network characteristics, etc.). Alternatively, the computer-readable computer-executable software/firmware code 585 may not be directly executed by the base station processor module 570, but rather cause the base station 105-d (e.g., when compiled and executed) to perform the various functions described.

The base station processor module 570 may include intelligent hardware devices such as a Central Processing Unit (CPU), microcontroller, ASIC, etc. The base station processor module 570 may process information received through the base station transceiver module, the base station communication module 565, and/or the network communication module 575. The base station processor module 570 may also handle: information to be sent to transceiver module 550 for transmission by antenna 550, information to be sent to base station communication module 565 for transmission to one or more other base stations 505-m and 505-n, and/or information to be sent to network communication module 575 for transmission to core network 530, core network 530 may be one or more aspects of core network 130 described with reference to fig. 1. The base station processor module 570 may, alone or in combination with the synchronization signal determination module 510, process various aspects of synchronization signaling operations for the UE for millimeter wave communications.

The base station transceiver module 550 may include a modem that modulates packets and provides the modulated packets to the base station antenna 545 for transmission, and demodulates packets received from the base station antenna 545. In some examples, base station transceiver module 550 may be implemented as one or more base station transmitter modules and one or more separate base station receiver modules. The base station transceiver module 550 may support communication in a first radio frequency band and/or a second radio frequency band. The base station transceiver module 550 may communicate bi-directionally with one or more UEs or devices (e.g., one or more of the UEs 115 described with reference to fig. 1, 2, 3, or 4) via the antenna 545. The base station 105-d may, for example, include multiple base station antennas 545 (e.g., antenna arrays). The base station 105-d may communicate with the core network 130-a through a network communication module 575. Base station 105-d may also communicate with other base stations, such as base stations 505-m and 505-n, using base station communication module 565.

Synchronization signal determination module 510 may perform and/or control some or all of the features and/or functions described with reference to fig. 2, 3, or 4 related to dynamic synchronization signaling operations (e.g., narrowband signal determination and adjustment, wideband signal determination and adjustment, etc.). The synchronization signal determination module 510 may include a power/bandwidth configuration module 595 that performs some or all of the features and/or functions of the synchronization signal determination module 510. In some examples, power/bandwidth configuration module 595 may determine a transmission power and/or bandwidth of a narrowband signal component and a wideband signal component in the synchronization signal. Power/bandwidth configuration module 595 may adjust parameters of the signal components based on the identified network characteristics of the millimeter wave communication network. The synchronization signal determination module 510, or a portion of the module 510, may include a processor, and/or some or all of the functions of the synchronization signal determination module 510 may be performed by the base station processor module 570 and/or in conjunction with the base station processor module 570. In some examples, the synchronization signal determination module 510 may be an example of the synchronization management module 210, 210-a, and/or 210-b described with reference to fig. 2, 3, and/or 4.

Fig. 6 is a flow diagram 600 illustrating aspects of a synchronization operation, in accordance with various aspects of the present disclosure. Diagram 600 may illustrate aspects of systems 100 and/or 500 described with reference to fig. 1 or 5, respectively. Diagram 600 includes a source cell 605 and a UE 610. The source cell 605 may be an example of one or more of the base stations 105 and/or devices 105 described above with reference to fig. 1, 2, 3, 4, and/or 5. The UE 610 may be an example of one or more of the UEs 115 described above with reference to fig. 1. In general, diagram 600 illustrates aspects for implementing dynamic directional synchronization signaling in a millimeter wave communication system. In some examples, a system device, e.g., one of UEs 115 and/or base stations 105, may execute one or more sets of codes to control the functional elements of the device to perform some or all of the functions described below.

At block 615, the source cell 605 determines a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communication. The signal components may include or convey system timing information, frame timing information, identification information, etc. for the source cell 605. At block 620, the source cell may determine or otherwise identify network characteristics of the millimeter-wave communication network. The network characteristics may include channel condition information, interference information, timing synchronization level information, density information, coverage area information, and the like. In some aspects, the source cell 605 may determine network characteristic information for each signal component, e.g., network characteristics for narrowband signal components and network characteristics for wideband signal components. Thus, the source cell 605 may determine the necessity, performance level, etc. of each of these signal components.

At block 625, the source cell 605 may adjust the narrowband signal component parameters and/or the wideband signal component parameters. The source cell may adjust the parameter based on the identified network characteristic. For example, the source cell 605 may adjust the transmit power discrimination between the narrowband signal and the wideband signal. The transmit power of the narrowband may be increased if the network characteristics indicate that the UE at the edge of the coverage area of the source cell 605 detects a decrease in the narrowband signal. In a fixed or limited transmit power environment, the transmit power associated with a wideband signal may be proportionally reduced.

As another example, the source cell 605 may adjust the transmit power and/or bandwidth of the narrowband signal and/or the wideband signal when the network characteristics indicate that there is at least a certain level of timing synchronization between UEs (e.g., UEs that have recently communicated with different base stations). When the network characteristics indicate that a wideband signal is being used for channel estimation by the UE and the channel estimation is: the source cell 605 may also increase the bandwidth of the broadband signal when the path loss is greater than a preset amount, the level of frequency selection exceeds a known value, or a combination thereof. In some examples, the source cell 605 may transmit a wideband signal on consecutive tones (or frequencies), on alternating tones, on non-uniform tones, or some other tone distribution scheme based on the identified network characteristics. Thus, source cell 605 may determine and adjust the narrowband signal component and the wideband signal component in the synchronization signal based on network characteristics of the millimeter wave communication network.

In some examples, the narrowband signal component may be a beacon. The wideband signal component may be a wideband signal and, in some cases, include a root value of a Zadoff-Chu sequence, or other information related to a Zadoff-Chu sequence, a pseudo-random noise (PR) sequence, or a maximum length sequence (m-sequence). At block 630, the source cell 605 may transmit the narrowband signal component and the wideband signal component in the synchronization signal using the adjusted parameters.

Fig. 7A through 7E are diagrams 700-a through 700-E, respectively, illustrating aspects in an example dynamic synchronization signal, in accordance with various aspects of the present disclosure. Diagram 700 may illustrate aspects of systems 100 and/or 500 described with reference to fig. 1 or 5, respectively. One or more of the base stations 105 and/or devices 105 described above with respect to fig. 1, 2, 3, 4, and/or 5 may implement aspects of diagram 700. In some examples, one or more sets of codes may be executed by a system device, e.g., one of UE 115 and/or base station 105, to control the functional elements of the device to perform some or all of the functions illustrated with respect to diagram 700.

Diagram 700 may include narrowband signal 705 and wideband signal 710 of a synchronization signal for millimeter wave communications. The narrowband signal 705 may generally have a greater amplitude than the wideband signal. According to aspects of the present disclosure, one or more parameters of the narrowband signal 705 and/or the wideband signal 710 may be adjusted based on the identified network characteristics of the millimeter-wave communication network. As shown in fig. 7A, the source cell may determine that narrowband signal 705-a and wideband signal 710-a have predefined transmit power levels/ratios and also have predefined bandwidths. If the network characteristics indicate that a predefined transmit power level/ratio and/or bandwidth is sufficient in view of current network conditions, the source cell may transmit the narrowband signal 705-a and the wideband signal 710-a at predefined levels.

However, as shown in fig. 7B, the source cell may adjust the transmit power level/ratio (when network characteristics indicate that such dynamic adjustment would be advisable). In the example shown in fig. 7B, the source cell may decrease the transmit power of narrowband signal 705-B and increase the transmit power of wideband signal 710-B. Conversely, as shown in fig. 7C, the source cell may increase the transmit power of the narrowband signal 705-C while decreasing the transmit power of the wideband signal 710-C based on network characteristics.

In other examples, the source cell may change the bandwidth of the narrowband signal 705 and/or the wideband signal 710 based on network characteristics. As shown in fig. 7D, the source cell may increase the bandwidth of the broadband signal 710-D (when network characteristics indicate that such dynamic adjustment would be advisable). Conversely, the source cell may reduce the bandwidth of the broadband signal 710-E (when the network characteristics suggest such an adjustment), as shown in fig. 7E.

Although fig. 7A through 7E show examples of dynamic adjustments to narrowband signal 705 and/or wideband signal 710, it is understood that other adjustments may be provided depending on the conditions of the millimeter-wave communication network. For example, in some network environments, it may be determined that narrowband signal 705 and/or wideband signal 710 are unnecessary and, therefore, eliminated from the synchronization signal.

Fig. 8 is a flow diagram 800 illustrating aspects of a synchronization operation, in accordance with various aspects of the present disclosure. Diagram 800 may illustrate aspects of systems 100 and/or 500 described with reference to fig. 1 or 5, respectively. Diagram 800 includes source cell 805, UE 810, additional UE 815, additional source cell 820, and base station 825. Source cell 805 and/or other source cells 820 may be examples of one or more of the following: the base station 105 and/or the device 105 described above with reference to fig. 1, fig. 2, fig. 3, fig. 4, and/or fig. 5. The UE 810 and/or other UEs 815 may be examples of one or more of the UEs 115 described above with reference to fig. 1. Base station 825 may be an example of a non-mmwave base station (e.g., an LTE/LTE-a base station). In general, diagram 800 illustrates aspects for implementing dynamic directional synchronization signaling in a millimeter wave communication system. In some examples, a system device, e.g., one of UEs 115 and/or base stations 105, may execute one or more sets of codes to control the functional elements of the device to perform some or all of the functions described below.

At block 830, the source cell 805 determines a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communication. The signal components may include or convey system timing information, frame timing information, identification information, etc. for the source cell 605. At block 840, the source cell may determine or otherwise identify a network characteristic of the millimeter wave communication network. The network characteristics may include channel condition information, interference information, timing synchronization level information, density information, coverage area information, and the like. In some aspects, the source cell 605 may determine network characteristic information for each signal component, e.g., network characteristics for narrowband signal components and network characteristics for wideband signal components. Thus, the source cell 605 may determine the necessity, performance level, etc. of each of these signal components.

In some examples, the source cell 805 may determine the network characteristic based at least in part on the feedback signal 835. For example, the source cell 805 may receive the feedback signal 835-a from other UEs 815 of the mmwave communication network. Other UEs 815 may include UEs that communicate with source cell 805 via millimeter wave communication. Other UEs 815 may provide their respective location information, channel condition information, interference level information, timing synchronization levels, etc. for the source cell 805. Additionally or alternatively, the source cell 805 may receive a feedback signal 835-b from another source cell. Another source cell may be a cell or base station in a millimeter wave communication network and may, for example, transmit its own channel condition information and/or relay such feedback signals from other UEs. Additionally or alternatively, the source cell 805 may receive a feedback signal 835-c from the base station 825. Base station 825 may be a non-millimeter wave base station and may transmit the feedback signal via a backhaul communication link. In some examples, the base station 825 may relay a feedback signal 835-c from a UE in communication with it but also located in the coverage area of the source cell 805. Thus, the source cell 805 may determine a wide variety of network characteristics to ensure optimal parameter adjustment for the narrowband signal and/or the wideband signal.

At block 845, the source cell 805 may adjust the narrowband signal component parameters and/or the wideband signal component parameters. The source cell may adjust the parameter based on the identified network characteristic. For example, the source cell 805 may adjust the transmit power distinction between narrowband signals and wideband signals. The source cell 805 may transmit the narrowband signal component and the wideband signal component in the synchronization signal using the adjusted parameters, at block 850.

Fig. 9 is a flow diagram illustrating an example of a method 900 for wireless communication in accordance with various aspects of the disclosure. For clarity, the method 900 is described below with reference to aspects of one or more of the base stations described with reference to fig. 1, 6, 7, or 8, and/or aspects of one or more of the devices described with reference to fig. 2, 3, 4, or 5. In some examples, a base station may execute one or more sets of codes to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform one or more of the functions described below.

At block 905, method 900 may include a base station identifying a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communication. The narrowband signals and the wideband signals may include or otherwise convey timing information, identification information, etc. for the base station. At block 910, the base station may identify one or more characteristics associated with the millimeter-wave communication network. Network characteristics may include, for example, path loss conditions, interference levels, timing synchronization levels, etc. The base station may determine network characteristics based on internal information (e.g., internal measurements, monitoring status, etc.) and/or based on feedback signals received from other components. At block 915, the base station may adjust at least one parameter of the narrowband signal component or the wideband signal component based on the network characteristic. For example, the base station may adjust the transmit power level or ratio, adjust the bandwidth, adjust the tone selection, and so on.

Operations at

blocks

905, 910, and 915 may be performed using the synchronization management module 210 and/or the synchronization signal determination module 510 described with reference to fig. 2, 3, 4, or 5.

Thus, the method 900 may provide wireless communication. It should be noted that the method 900 is merely one implementation and that the operations of the method 900 may be rearranged or otherwise modified such that other implementations are possible.

Fig. 10 is a flow diagram illustrating an example of a method 1000 for wireless communication, in accordance with various aspects of the present disclosure. For clarity, the method 1000 is described below with reference to aspects of one or more of the base stations described with reference to fig. 1, 6, 7, or 8, and/or aspects of one or more of the devices described with reference to fig. 2, 3, 4, or 5. In some examples, a base station may execute one or more sets of codes to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform one or more of the functions described below.

At block 1005, method 1000 may include a base station identifying a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communication. The narrowband signals and the wideband signals may include or otherwise convey timing information, identification information, etc. for the base station. At block 1010, the base station may identify one or more characteristics associated with the millimeter-wave communication network. Network characteristics may include, for example, path loss conditions, interference levels, timing synchronization levels, etc. The base station may determine network characteristics based on internal information (e.g., internal measurements, monitoring status, etc.) and/or based on feedback signals received from other components. At block 1015, the base station may adjust a transmit power discrimination parameter of the narrowband signal component or the wideband signal component based on the identified network characteristic. For example, the base station may increase the transmit power of the narrowband signal component and decrease the transmit power of the wideband signal component, or vice versa.

At block 1020, the base station may transmit the narrowband signal component and the wideband signal component in the synchronization signal using the adjusted parameters. In some examples, the base station may directionally transmit the signal components via the beamformed signals.

Operations at

blocks

1005, 1010, 1015, and 1020 may be performed using the synchronization management module 210 and/or the synchronization signal determination module 510 described with reference to fig. 2, 3, 4, or 5.

Thus, the method 1000 may provide wireless communication. It should be noted that the method 1000 is just one implementation and that the operations of the method 1000 may be rearranged or otherwise modified such that other implementations are possible.

Fig. 11 is a flow diagram illustrating an example of a method 1100 for wireless communication, in accordance with various aspects of the disclosure. For clarity, the method 1100 is described below with reference to aspects of one or more of the base stations described with reference to fig. 1, 6, 7, or 8, and/or aspects of one or more of the devices described with reference to fig. 2, 3, 4, or 5. In some examples, a base station may execute one or more sets of codes to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform one or more of the functions described below.

At block 1105, the method 1100 may include a base station identifying a narrowband signal component and a wideband signal component in a synchronization signal for millimeter wave communications. The narrowband signals and the wideband signals may include or otherwise convey timing information, identification information, etc. for the base station. At block 1110, a base station may identify one or more characteristics associated with a millimeter wave communication network. Network characteristics may include, for example, path loss conditions, interference levels, timing synchronization levels, etc. The base station may determine network characteristics based on internal information (e.g., internal measurements, monitoring status, etc.) and/or based on feedback signals received from other components. At block 1115, the base station may adjust a bandwidth parameter of the wideband signal component based on the identified network characteristic. For example, the base station may increase or decrease the bandwidth of the wideband signal component.

The base station may transmit the narrowband signal component and the wideband signal component in the synchronization signal using the adjusted parameters, at block 1120. In some examples, the base station may directionally transmit the signal components via the beamformed signals.

Operations at blocks 1105, 1110, 1115, and 1120 may be performed using the synchronization management module 210 and/or the synchronization signal determination module 510 described with reference to fig. 2, 3, 4, or 5.

Thus, the method 1100 may provide wireless communication. It should be noted that the method 1100 is merely one implementation and that the operations of the method 1100 may be rearranged or otherwise modified such that other implementations are possible.

In some examples, aspects from two or more of

methods

900, 1000, and/or 1100 may be combined. It should be noted that the

methods

900, 1000, and 1100 are merely exemplary implementations, and the operations of the methods 900 through 1100 may be rearranged or otherwise modified such that other implementations are possible.

The techniques described herein may be used for various wireless communication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other systems. The terms "system" and "network" are generally used interchangeably. A CDMA system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), and so on. CDMA2000 covers IS-2000, IS-95 and IS-856 standards. IS-2000 releases 0 and A are commonly referred to as CDMA 20001X, 1X, etc. IS-856(TIA-856) IS commonly referred to as CDMA 20001 xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes wideband CDMA (wcdma) and other variants of CDMA. TDMA systems may implement wireless technologies such as global system for mobile communications (GSM). OFDMA systems may implement methods such as Ultra Mobile Broadband (UMB), evolved UTRA (E-UTRA), IEEE 802.11(Wi-Fi), IEEE 802.16(WiMAX), IEEE802.20, Flash-OFDM^TMAnd so on. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) and LTE-advanced (LTE-A) are new versions of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE-A, and GSM are described in literature from an organization named "third Generation partnership project" (3 GPP). CDMA2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3GPP 2). The techniques described herein may be used for the above-described systems and wireless technologies as well as other systems and wireless technologies, including cellular (e.g., LTE) communications over unlicensed and/or shared bandwidth. However, the above description describes an LTE/LTE-a system for purposes of example, and LTE terminology is used in much of the description above, but the techniques are applicable beyond LTE/LTE-a applications.

The detailed description set forth above in connection with the appended drawings is intended as a description of examples and is not intended to represent the only examples that may be implemented or within the scope of the claims. The terms "example" and "exemplary" when used in this specification mean "serving as an example, instance, or illustration," and not "preferred" or "superior to other examples. The detailed description includes specific details for the purpose of providing an understanding of the described technology. However, the techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

Information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the present disclosure may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope and spirit of the disclosure and the following claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. Features used to implement a function may also be physically located at various locations, including being distributed such that a portion of a function is implemented at a different physical location. As used herein, including the claims, when the term "and/or" is used in reference to a list of two or more items, it means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a combination is described as containing components A, B and/or C, the combination may contain a alone, B alone, C, A and B alone, a and C alone, B and C alone, or A, B and C together. In addition, as used herein, including the claims, a "or" (e.g., a list of items prefaced by a phrase such as "at least one of" or "one or more of") in a list of items indicates a discrete list, such that, for example, a list of "A, B or at least one of C" means a or B or C or AB or AC or BC or ABC (i.e., a and B and C).

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, computer-readable media can comprise RAM, ROM, EEPROM, flash memory, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication, comprising:

determining a narrowband signal component and a wideband signal component of a synchronization signal of a millimeter wave communication network;

identifying one or more characteristics associated with the millimeter wave communication network; and

selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic,

wherein adjusting the at least one parameter comprises:

adjusting a transmit power discrimination between the narrowband signal component and the wideband signal component.

2. The method of claim 1, wherein the transmit power distinction comprises a ratio of a first transmit power of the narrowband signal component to a second transmit power of the wideband signal component.

3. The method of claim 1, further comprising:

identifying, by one or more User Equipments (UEs) located at an edge of a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a detected reduction of the narrowband signal component;

increasing a first transmit power of the narrowband signal component based at least in part on the identified reduction; and

reducing a second transmit power of the wideband signal component based at least in part on the identified reduction.

4. The method of claim 1, further comprising:

receiving information indicating a predefined level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component; and

selectively adjusting the parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on a level of the timing synchronization.

5. The method of claim 1, wherein the one or more characteristics comprise one or more of: a level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a false alarm rate associated with the one or more UEs detecting an incorrect synchronization signal, a distribution of UEs entering the coverage area of the source, or a combination thereof.

6. The method of claim 1, wherein adjusting the at least one parameter comprises:

adjusting the bandwidth of the wideband signal component.

7. The method of claim 6, further comprising:

increasing the bandwidth of the wideband signal component based at least in part on a determination that a path loss is above a predefined threshold or a level of frequency selection exceeds a predefined value.

8. The method of claim 6, further comprising:

increasing the bandwidth of the wideband signal component based at least in part on a determination that the wideband signal component is being used by at least one user equipment for channel estimation.

9. The method of claim 1, wherein adjusting the at least one parameter comprises at least one of:

transmitting the wideband signal component on consecutive tones, transmitting the wideband signal component on alternating tones, transmitting the wideband signal component on non-uniform tones, or a combination thereof.

10. The method of claim 1, wherein identifying the one or more characteristics comprises one or more of:

receive feedback signals from one or more User Equipments (UEs) communicating via the millimeter wave communication network, receive feedback signals from one or more other sources in the millimeter wave wireless communication system, receive feedback signals from one or more base stations in a non-millimeter wave wireless communication system, or a combination thereof.

11. The method of claim 1, wherein the narrowband signal component comprises a beacon signal and the wideband signal component comprises a wideband signal.

12. The method of claim 11, wherein the wideband signal comprises a Zadoff-Chu sequence.

13. The method of claim 1, wherein the narrowband signal component and the wideband signal component of the synchronization signal are directionally transmitted via one or more beamformed signals.

14. An apparatus for wireless communication, comprising:

a processor;

a memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to:

wherein adjusting the at least one parameter comprises: adjusting a transmit power discrimination between the narrowband signal component and the wideband signal component.

15. The apparatus of claim 14, wherein the transmit power distinction comprises a ratio of a first transmit power of the narrowband signal component to a second transmit power of the wideband signal component.

16. The apparatus of claim 14, further comprising instructions executable by the processor to:

17. The apparatus of claim 14, further comprising instructions executable by the processor to:

18. The apparatus of claim 14, wherein the one or more characteristics comprise one or more of: a level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a false alarm rate associated with the one or more UEs detecting an incorrect synchronization signal, a distribution of UEs entering the coverage area of the source, or a combination thereof.

19. The apparatus of claim 14, wherein the instructions executable by the processor to selectively adjust parameters of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic comprise instructions executable by the processor to:

adjusting the bandwidth of the wideband signal component.

20. The apparatus of claim 19, further comprising instructions executable by the processor to:

21. The apparatus of claim 19, further comprising instructions executable by the processor to:

22. An apparatus for wireless communication, comprising:

means for determining a narrowband signal component and a wideband signal component of a synchronization signal of a millimeter wave communication network;

means for identifying one or more characteristics associated with the millimeter-wave communication network; and

means for selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic,

wherein the means for selectively adjusting a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic comprises:

means for adjusting a transmit power discrimination between the narrowband signal component and the wideband signal component.

23. The apparatus of claim 22, wherein the transmit power distinction comprises a ratio of a first transmit power of the narrowband signal component to a second transmit power of the wideband signal component.

24. The apparatus of claim 22, further comprising:

means for identifying, by one or more User Equipments (UEs) located at an edge of a coverage area of a source transmitting the narrowband signal component and the wideband signal component, a detected reduction of the narrowband signal component;

means for increasing a first transmit power of the narrowband signal component based at least in part on the identified reduction; and

means for reducing a second transmit power of the wideband signal component based at least in part on the identified reduction.

25. The apparatus of claim 22, further comprising:

means for receiving information indicating a predefined level of timing synchronization between one or more User Equipments (UEs) located within a coverage area of a source transmitting the narrowband signal component and the wideband signal component; and

means for selectively adjusting the parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on a level of the timing synchronization.

26. A non-transitory computer-readable medium storing computer-executable code for wireless communication, the code executable by a processor to:

wherein the code executable by the processor to selectively adjust a parameter of at least one of the narrowband signal component and the wideband signal component based at least in part on the identified characteristic comprises code executable by the processor to: